Re: Re: Searching MOS Note on dynamic sampling

From: <l.flatz_at_bluewin.ch>
Date: Tue, 3 Mar 2020 14:20:13 +0100 (CET)
Message-ID: <1511576730.24721.1583241613928_at_bluewin.ch>





Hi Mladen,
thanks, I know what dynamic sampling is. I had deep level questions on how it works internally. You will find the questions below.
Thanks and Reagrds
Lothar
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Von : gogala.mladen_at_gmail.com
Datum : 01/03/2020 - 02:12 (MN)
An : oracle-l_at_freelists.org
Betreff : Re: Searching MOS Note on dynamic sampling Hi Lothar!
This is not a MOS note but Nigel Baylis's blog:
https://blogs.oracle.com/optimizer/dynamic-sampling-and-its-impact-on-the-optimizer There is also an old Oracle Magazine Article by The Oracle Master (Tom for short) Kyte: https://blogs.oracle.com/oraclemagazine/on-dynamic-sampling This is one of the very few articles by Tom Kyte that have survived his retirement. Regards
 On 2/28/20 3:22 AM, Lothar Flatz wrote:  

  Hi Guys,      

I colleague of mine told me that he read a MOS Note that was describing the details of the way dynamic sampling is done.  The note was mentioning that only bitmap blocks are sampled and blocks less than 25% full are considered empty.  In that same note also deferred segment creation is mentioned.  As my colleague is very experienced I believe is memory is correct.  However, we cannot find that note any more.  

 Can somebody point us to the doc?    

 Regards and thank    

 Lothar        

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Mladen Gogala
Database Consultant
Tel: (347) 321-1217

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http://www.freelists.org/webpage/oracle-l Received on Tue Mar 03 2020 - 14:20:13 CET

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